Drill for mining purposes



(No Model.)

W. H. LABIMER. DRILL FOR MINING PURPOSES.

Patented July 5, 1887.

WITNESSES N. FETERS, Phnlo-Lilhogmphur, Waafinglon. D. (1

UNITED STATES PATENT OFFICE,

\VILLIAM H. LARIMER, OF TERRE HAUTE, INDIANA.

DRILL FOR MINING PURPOSES.

SPECIFICATION forming part of Letters Patent No. 365,925, dated July 5,1887.

Application filed February 23, 1887. Serial No. 228,607.

To all whom, it may concern.-

art to which it appertains to make and use the same.

This invention relates to certain new and useful improvements in drillsfor mining purposes; and it consists,substantially,in the same asconstructed, and in such peculiar arrangement and combinations of partsas 'will hereinafter be more particularly described, and pointed out inthe claims.

Heretofore in boring rock and coal deposits for creating a cavity orrepository for a blasting compound by which to disintegrate or break upthe mass into smaller fragments it has been customary in many instancesto resort to the use of drills of-various forms of construction, andwhich in many instances produce or form openings whose diameter is ofequal extent throughout, and frequently the drills have to be driven into a considerable depth to produce openings large enough for thepurposes required.

The object of the present invention is tosupply a device by which theinterior extremity of the openings may be increased in capacity, wherebya greateramount of blasting compound may be inserted within amass ofrock or coal deposit,to thereby more fully insure an equal separation ordisintegration of the mass, all as will more fully hereinafter appearwhen taken in connection with the accompanying drawings, wherein Figure1 represents a view of my improved drill as it appears in operation; andFig. 2 is a view in detail of a portion thereof, showing the movableblades in an open position, and more fully indicating the constructionthereof. Fig. 3 is a side View of Fig. 2. Fig. l is a similar view toFig. 2, representing the movable blade as when closed, and Fig. 5 isaside view thereof.

Reference being had to the several parts by the letters marked thereon,A represents a drill embodying myimprovements, the same being (N0model.)

preferably of the well-known anger style or form, and which, in order toillustrate one manner of using the same, is shown supported or mountedin suitable bearings, B, the drill being provided with a handle orcrank, O, by which it is operated to be turned or revolved. The end ofthe drill is formed with a screwpoint, a, by which it is readilyinserted or started, and it is also squared or flattened, as at b, andis formed at opposite sides with lugs or stops 0 c, for a purpose to behereinafter set forth. I

D D represent blades or knives pivoted to the opposite sides of theflattened portion 1), the same having formed on their inner faoesa ribor flange, d. The opposite or corresponding edges of these knives arecurved. or beveled, as at e, by which they are caused to separate orspread apart when brought into contact with the walls of the cavity thatis to be enlarged, so as to obtain the proper position thereof to effecta cutting action. Thelugs or shoulders c c serve to prevent the knivesor blades from beingspread too far backward, and they also serve toreceive or sustain a part of the pressure necessarily exerted in the operation of the drill, thereby relieving the pivot f from strain andpreventing breakage thereof. The flanges or ribs d are for the purposeof preventing the blades from closing too far in or across each other bycoming in contact with or abutting against the screw-point a; and it.will be seen on reference to Fig. 4 that when the blades are closedtogether their curved cutting-edges produce a notch or V- shapedopening, by which it is evident that when the drill is inserted in anopening, 9, previously formed in a mass of coal or rock, and the samepressed against the rear wall thereof,the said knives or blades will becaused to gradually spread outward as the drill is being operated.

The operation of myinvention is as follows: lVhen it is desired toincrease or enlarge the capacity of a drill-opening in a mass of rock orcoal, the drill A is projected into the opening and the same revolved orturned in the ordinary manner of operating a drill, and gradually aspressure is exerted the'knives will'cut away the portions around theopening with which they come in contact until they are spread apart totheir fullest extent and made to rest or bear against the shoulders c 0,and it is evident that the said blades will act to cut out or increasethe size of the cavity. In operation the screw-point a is continuallyentering the mass in advance of the blades, thus acting to start'a wayfor and as sist in the operation of said blades in that it breaks orloosens the particles of the mass.

From the foregoing description it is thought the construction andoperation ofniy improved drill will be thoroughly understood, and Idesire to state that I do not wish to be understood as limiting myselfto the details of construction' and arrangements of parts as shown, forit is evident that various modifications or changes thereof could beresorted to and still come within the scope of my invention.

Having thus described my invention, what I claim as new, and desire tosecure by Letters Patent, is

1. A drill of the character described, having knives or blades pivotedto its opposite sides whose corresponding edges are curved or beveled,the same being formed with the screw-point a, designed to operate inadvance of the blades when revolved or rotated, and shoulderscc,limiting the spread of the knives, substantially as specified.

2. The combination, with thedrill formed with screw-point a, designed tooperate in advance of the blades when revolved or rotated, and shouldersc c, limiting the spread of the blades, of the oppositely-pivoted bladesB D, having ribs d on their inner faces designed to abut against thepoint a for preventing the said blades from crossing each other whenclosed together, substantially as described.

3. The oombinatiomwith a drill of the character described, formed withlugs or shoulders c c and screw-point a, and flattened, as at b, ofknives D D, pivotally attached and formed with ribs (1 on their innerfaces, substantially as set forth.

In testimony that I claim the foregoing as my own I affix my signaturein presence of two witnesses.

WM. H. LARIMER.

Witnesses: V

W. H. SOALE, A. B. WILLIs.

